Is the 355 based on the 348?

And thats a big part of why the 95s run so much better than the 69-99s.

 

Interesting... thanks for the info.

But why do you say the 95's run so much better? Do they rev. easier or what? Better acceleration? Higher top speed? I understand they make 5 or 10 hp more which is nice but I can't imagine that would be felt as something that runs so much better.

 

Features

Body type: Convertible
Engine: 8 CYLINDERS 3.5 Liters
Exterior color: Black
Transmission: Manual
Fuel type: Steam
Interior color: Black
Drivetrain: --
Disability equipped: --
Certification: --​

Oh, does it not? I've seen journalist reviews and also classified adverts claiming that it did have traction control... I never really thought to look into it more deeply.

Thanks for the info.

All the best,
Andrew.

 

...... that resonator was put there to 'muffle' intake noise ......... because when both banks were merged, the sound freqs changed .........

lol ..........

Yeah they sometimes say it has 'variable' valve timing ....... when it is really 'varied' valve timing ....... the two outers open just before the center and close just after the center to create a 'swirl' ...........

.

 

This list of 'facts' I thought I knew about the 355 is getting shorter and shorter by the minute...

Are there any other common misconceptions I probably picked up somewhere?

 

Early 355's had the option to delete the power steering at the factory. I think you got a rack with a different ratio then (maybe was an option throughout the years??).

Also, Euro 355's, as you may know, would allow you to turn off the ABS (don't know if the 348 had that ability or not). No turn-off button on U.S. models :-( no doubt because of some silly U.S. regulation.

Active suspension gives it a quite decent ride quality for the type of car it is. Allows you to tolerate it for longer journeys than with many other sports cars.

 

??


Mitch Alsup Mitch Alsup
Formula 3
Not Subscribed
"And thats a big part of why the 95s run so much better than the 69-99s."

 

lol ..... I saw that too ........ but .......... reversing two numbers ..... well .... happens ......

.

 

Well... I wasn't really interested in the reversed numbers but I was interested in getting an answer as to how a 95 "runs so much better." One or two other questions were not really answered either. Guess I just like facts to back up statements

 

The 1995s use Motronic 2.7 which only has O2 sensors in front of the cats. Later years (excluding Challenge 355s) have Motronic 5.2, which have O2 sensors in front and behind the cats...making fuel/air adjustments based on 4 O2 sensors is more problematic as cars age than is doing the same from just 2 fronts.

M5.2 is *known* to be a problematic computer.

M2.7 was used for years with extreme success in the Ferrari F50, 456, 348s, 512TRs, and even some of the last Mondial Ts.

 

I'm familiar with the differences between the 2.7 and 5.2. I don't think an ECU that sometimes has more problems is the same as saying one version "runs so much better" than the other.

Are four o2 sensors actually used on the 5.2 to adjust air/fuel or are the secondary 02 sensors simply there to let the ECU know when the cats. are no longer as efficient as they should be?

How do you define "extreme success?" ("M2.7 was used for years with extreme success in the Ferrari F50, 456, 348s, 512TRs, and even some of the last Mondial Ts.") Would seem to imply 5.2 355's were major failures.

 

M2.7: 2nd fastest qualifying time at Le Mans 1994. 6th place finish in class (348). Plus, the F50 has performance that is still competitive 15 years later.


M5.2 is problematic. It was the first generation of new pollution control systems, plus it had OBD2 diagnostics slapped on it.

 

I'm reading some nonsense here (again)...

"It was the first generation of new pollution control systems, plus it had OBD2 diagnostics slapped on it"

OBD2 is what made it the first generation of NEW pollution control systems (not "plus it had OBD2 diagnostics slapped on it").

What's with the silly quotes about race finishes? Do you suppose an F50 today that had a 5.2 Motronic might be competitive?

And, once again, Are four o2 sensors actually used on the 5.2 to adjust air/fuel or are the secondary 02 sensors simply there to let the ECU know when the cats. are no longer as efficient as they should be?

 

No.

OBD2 is a diagnostic, communication system, and storage system. Flash memory. Faster data transfer. Different communication protocol than OBD1, too.

The new pollution control came from the mandatory O2 sensors on both ends of the cats. Different internal firmware coding and different engine management adjustments and different sensors to get the new polltuion controls.

So the actual pollution control is different in M5.2 from that of adding OBD2 capabilities.

If you look at the 1995 Corvettes, for example, they had OBD2 diagnostics, but did *not* have front and rear O2 sensors. So you can have the new generation of OBD2 diagnostics/communications without having the new pollution controls.

Ergo OBD2 is *not* synonomous with the new pollution controls. Sure, a lot of new computers included both, but that was not the only option. They aren't the same things.

 

There is nothing wrong with 5.2 motronic as a 'system' when the the engine is 'mechanically sound' with proper cam timing ....... if any problems arise it is because the are physical wire, connector and or sensor issues. A lot of this can be remedied with a connector upgrade like Dave Helm's connector kit.

Ferrari does not use the best wire quality ..... so when it spends enough time in a hot engine compartment, the insulation/boots degrade leaving the conductors vulnerable to accelerated aging. This affects the delicate signals the ECU needs for optimal engine management.

The two post cat o2 sensors have only one job and that is to monitor catalyst health.

The reason people think 2.7 is better is because it is simpler and more people know how to modify/adjust it ....... one of the reasons the 2.7 355 has a few more HP because it has a better intake configuration with two MAFs. One can make up for this on the 5.2 by installing hi-flow air box tops or the big gruppeB intake, both of which have a higher flow capacity.

 

I would add that more people also know how to reset M2.7. In contrast, M5.2 stores error codes and new fuel/air tables in flash memory that can survive a disconnected car battery.

 

This is true ..... but codes and other memory can be 'reset' with proper equipment ....

I really liked the OBDII Motronic and wiring of my 993TT ...... it was very 'consistent' and used high quality wire/components .... when compared to my 355 .....